Scan the devices listed in /proc/partitions

During the commands:
	- btrfs filesystem show
	- btrfs device scan
the devices "scanned" are extracted from /proc/partitions. This
should avoid to scan devices not suitable for a btrfs filesystem like cdrom
and floppy or to scan not existant devices.
The old behavior (scan all the block devices under /dev) may be
forced passing the "--all-devices" switch.

1 files changed, 16 insertions, 11 deletions

diff --git a/man/btrfs.8.in b/man/btrfs.8.in
index e830abd4..ab9f44f5 100644
--- a/man/btrfs.8.in
+++ b/man/btrfs.8.in
@@ -31,9 +31,9 @@ btrfs \- control a btrfs filesystem
 .PP
 \fBbtrfs\fP \fBfilesystem defragment\fP\fI <file>|<dir> [<file>|<dir>...]\fP
 .PP
-\fBbtrfs\fP \fBdevice scan\fP\fI [<device>...]\fP
+\fBbtrfs\fP \fBdevice scan\fP\fI [--all-devices|<device> [<device>...]]\fP
 .PP
-\fBbtrfs\fP \fBdevice show\fP\fI [<device>|<uuid>|<label>]\fP
+\fBbtrfs\fP \fBdevice show\fP\fI [--all-devices|<uuid>|<label>]\fP
 .PP
 \fBbtrfs\fP \fBdevice add\fP\fI <device> [<device>...] <path> \fP
 .PP
@@ -153,11 +153,6 @@ use it if you use snapshots, have de-duplicated your data or made copies with
 List the recently modified files in a subvolume, after \fI<last_gen>\fR ID.
 .TP
 
-\fBdevice scan\fR \fI[<device>...]\fR
-Scan devices for a btrfs filesystem. If no devices are passed, \fBbtrfs\fR scans
-all the block devices.
-.TP
-
 \fBfilesystem sync\fR\fI <path> \fR
 Force a sync for the filesystem identified by \fI<path>\fR.
 .TP
@@ -202,9 +197,11 @@ NOTE: Currently there are the following limitations:
 - the filesystem should not have more than one device.
 .TP
 
-\fBfilesystem show\fR [<uuid>|<label>]\fR
-Show the btrfs filesystem with some additional info. If no UUID or label is
-passed, \fBbtrfs\fR show info of all the btrfs filesystem.
+\fBfilesystem show\fR [--all-devices|<uuid>|<label>]\fR
+Show the btrfs filesystem with some additional info. If no \fIUUID\fP or 
+\fIlabel\fP is passed, \fBbtrfs\fR show info of all the btrfs filesystem.
+If \fB--all-devices\fP is passed, all the devices under /dev are scanned;
+otherwise the devices list is extracted from the /proc/partitions file.
 .TP
 
 \fBdevice balance\fR \fI<path>\fR
@@ -218,7 +215,15 @@ Add device(s) to the filesystem identified by \fI<path>\fR.
 
 \fBdevice delete\fR\fI <dev> [<dev>..] <path>\fR
 Remove device(s) from a filesystem identified by \fI<path>\fR.
-.PP
+.TP
+
+\fBdevice scan\fR \fI[--all-devices|<device> [<device>...]\fR
+If one or more devices are passed, these are scanned for a btrfs filesystem. 
+If no devices are passed, \fBbtrfs\fR scans all the block devices listed
+in the /proc/partitions file.
+Finally, if \fB--all-devices\fP is passed, all the devices under /dev are 
+scanned.
+.TP
 
 \fBscrub start\fP [-Bdqru] {\fI<path>\fP|\fI<device>\fP}
 Start a scrub on all devices of the filesystem identified by \fI<path>\fR or on